(2 of 2)
In Japan the obliteration of Hiroshima did not at first yield conclusive results. Japanese scientists assessing the Hiroshima damage doubted that the Americans could possibly have harvested enough radioactive material to make more than a few bombs. It was even likely, they said, that Hiroshima was a one-off stunt that could not be repeated. (This deprecation of the magnitude of the U.S. Bomb program suggests how ineffective a demonstration would have been.) Only after the Soviet declaration of war against Japan on Aug. 8 and the second nuclear attack on Nagasaki on Aug. 9 did Emperor Hirohito, in an exceedingly rare display of direct political command, overrule some of his own military leaders, who advocated an apocalyptic fight to the finish. Citing the unprecedented destructive power of the atom bombs, he declared, "I swallow my own tears and give my sanction to the proposal to accept the Allied proclamation"--which called for Japan's unconditional surrender.
The atom bombs thus undoubtedly sped the conclusion of the war against Japan. They also ignited a moral controversy that has endured to this day. That controversy concerns an issue much larger than the bombs themselves, one whose origins date from well before the war.
In 1933 the U.S. War Department sponsored a design competition for a new kind of weapons system--the strategic bomber. While Germany, Japan and Italy bombed civilians in World War II, only the U.S. and Britain configured their forces and defined their war-fighting doctrines around the central element of a massive strategic air arm designed to carry the battle to the enemy's civilian society. In Europe the U.S. B-17 and B-24 bomber fleets made a considerable effort to restrict their attacks to high-value economic and military targets. But in the endgame of the war against Japan, long-range B-29 bombers systematically undertook fire-bombing raids that consumed 66 of Japan's largest cities and killed as many as 900,000 civilians--many times the combined death tolls of Hiroshima and Nagasaki.
The weapons that incinerated those two unfortunate cities represented a technological innovation with fearsome consequences for the future of humanity. But the U.S. had already crossed a terrifying moral threshold when it accepted the targeting of civilians as a legitimate instrument of warfare. That was a deliberate decision, indeed, and it's where the moral argument should rightly focus.
Kennedy teaches history at Stanford University and is working on a book about the American national character